1. Field of the Invention
The present invention relates generally to a method and device for transilluminating a tubular tissue within the body of a patient.
2. Prior Art
Catheters such as transilluminating light delivery catheters, endoscopes, bougies and the like are frequently introduced into a lumen of the body for the purpose of transillumination. Such catheters include light delivery catheters having a diffuser tip on distal portion thereof. Such catheters are useful for delivering light to a distal portion of the body for performing phototherapeutic procedures as well as transillumination.
The majority of current standard operating room light sources have only a single light output port. Such sources are not designed for multiple catheter illumination. The operating room, therefore, must have a separate light source for each illuminator in more than one illuminator is to be employed in a procedure. There are a few light source manufacturers providing dual ports for dual illumination, however most multi-port sources permit only one catheter at a time to be attached thereto. Thus, if it is desired to have more than one tubular tissue transilluminated simultaneously, it is necessary to have more than one illuminating source to provide the power necessary for such transillumination.
Prior art fiber optics for illuminating small tissues have a relatively small cross-sectional diameter and the input end is flat cut to reduce reflection and loss of the input light from the source of light. The flat cut input aperture for such fibers limits the amount of light power which can be coupled into the catheter from a conventional non-collimated light source. In order to couple sufficient power into a light delivery catheter for certain applications such as transillumination, a complicated lensing system must be interposed between the light output port of the light source and the light input end of the fiber optic or fiber optic bundle within the catheter.
Martinez, in U.S. Pat. No. 5,437,290, provides a fiber optic having a flared proximal end suitable for collecting light from a single source of divergent or collimated light. The connector for attaching the proximal light-receiving end of the fiber to the light source requires collimating optics to be installed in optical alignment within the connector. In addition, the catheter can supply power to only a single fiber optic for transillumination.
During the performance of laparoscopic procedures such as surgery on or around the ureters, it is desirable to provide dual transillumination of the ureters in order to clearly visualize the operative field laparoscopically. In order to do so in accordance with the prior art, one must have separate delivery fibers attached to separate light sources threaded through the urethra into the bladder and transversing the ureters prior to initiating surgical procedures. It would, therefore, be desirable to have single optical fiber bundle which can be inserted the bladder through the urethra and which upon entry into the bladder could be made to bifurcate and diverge to form separate transilluminating fibers to simultaneously transilluminate both ureters from a single light source.
The Martinez patent referenced above contemplates a fiber optic having a proximal end which receives light from a rod having a flat face in optical communication with the proximal end of the fiber. The proximal end of the fiber optic is heated and shaped to form a lens. The lens is a-refractive lens; the radius or curvature of which is adapted to focus collimated light incident thereupon into the fiber optic for conduction along the length thereof to the distal end. The light incident upon the flared proximal end of the fiber optic is substantially collimated. It is desirable to provide a right delivery catheter wherein the light input end is adapted to receive light from a non-collimated source.